Position the camshaft timing slots below the centerline of the camshaft to correctly fit the special tools and install the special tools on the front of the RH cylinder head.

Fig. Position the camshaft timing slots below the centerline of the camshaft to correctly fit the special tools and install the special tools on the front of the RH cylinder head-4.0L (VIN E) SOHC engine

Remove the RH camshaft tensioner.

Install the special tool, 303-571, in place of the RH camshaft tensioner.

Repeat the above procedure for the LH cylinder head, using the appropriate special tools where needed.

Install the camshaft roller followers.

4.6L (VIN H) DOHC Engine

Before servicing the vehicle, refer to the -Precautions- section.

Remove the crankshaft sensor ignition pulse ring.

WARNING

Since the engine is not free-wheeling, timing procedures must be followed exactly or piston and valve damage can occur.

WARNING

Unless otherwise instructed, at no time when the timing chains are removed and the cylinder heads are installed is the crankshaft or the camshaft to be rotated. Severe piston and valve damage will occur.

Using special tool 303-448, position the crankshaft with the keyway at the 12 o'clock position.

Install special tool 303-446.

Fig. Timing chains and related parts-4.6L DOHC engine

Fig. Secondary timing chains and related parts-4.6L DOHC engine

Remove the timing chain tensioning system from both timing chains.

Remove the bolts.

Remove the timing chain tensioners.

Remove the timing chain tensioner arms.

Remove the right timing chain tensioner arm.

Remove the left timing chain tensioner arm.

Remove the right camshaft sprocket mounting bolt.

Remove the right camshaft sprocket washer.

Remove the right camshaft sprocket.

Remove the left camshaft sprocket mounting bolt.

Remove the left camshaft sprocket washer.

Remove the crankshaft gear.

Remove the left timing chain.

Remove the left camshaft sprocket.

Remove the left timing chain guide.

Remove the right timing chain guide.

Remove the right intake camshaft gear mounting bolt.

Remove the right intake camshaft gear washer.

Remove the right intake camshaft gear spacer.

Remove the left intake camshaft gear mounting bolt.

Remove the left intake camshaft gear washer.

Remove the left intake camshaft gear spacer.

Remove the left secondary timing chain tensioner.

Remove the right secondary timing chain tensioner.

Remove the right exhaust secondary camshaft sprocket.

Remove the right secondary camshaft timing chain.

Remove the right intake secondary camshaft sprocket.

Remove the left intake secondary camshaft sprocket.

Remove the left exhaust secondary camshaft sprocket.

Remove the left secondary camshaft timing chain.

To install:

Installation is the reverse of the removal procedure. Observe the following notes:

Timing Drive Components Installation

Compress the tensioner and install the retaining pin. Install the tensioners.

CAUTION

Timing marks must be at the 12 o'clock position and indexed at the 6 o'clock position.

Install the camshaft sprockets and chain as an assembly.

Install special tool 303-446.

Fig. Install special tool 303-446

Fig. Install the camshaft sprockets and chain as an assembly

Install the camshaft spacer, washer and bolt, and hand-tighten the bolt.

Install the camshaft gear, washer and bolt, and hand-tighten the bolt.

Tighten the bolts in two stages:

CAUTION

Timing chain procedures must be followed exactly or damage to valves and pistons will result.

CAUTION

Do not compress the ratchet assembly. This will damage the ratchet assembly.

Stage 1: Tighten to 30 ft. lbs. (40 Nm).

Stage 2: Tighten an additional 90 degrees.

On engine with ratcheting timing chain tensioners only.

Compress each tensioner plunger, using an edge of a vise.

Using a small screwdriver or pick, push back and hold the ratchet mechanism.

While holding the ratchet mechanism, push the ratchet arm back into the tensioner housing.

Install a paper clip into the hole of each tensioner housing to hold the ratchet assembly and plunger in during installation. Remove the tensioner from the vise.

CAUTION

The timing chain procedures must be followed exactly or damage to valves and pistons will result.

On engine with non-ratcheting timing chain tensioners only.

Compress each tensioner plunger, using a vise.

Install a retaining clip on each tensioner to hold the plunger in during installation.

If the copper links are not visible, mark one link on one end and one link on the other end, and use as timing marks.

Fig. If the copper links are not visible, mark one link on one end and one link on the other end, and use as timing marks<4.6L DOHC engine

Install the timing chain guides.

Rotate the left camshaft sprocket until the timing mark is approximately at the 12 o'clock position. Rotate the right camshaft timing sprocket until the timing mark is approximately at the 11 o'clock position.

CAUTION

Unless otherwise instructed, at no time when the timing chains are removed and the cylinder heads are installed is the crankshaft or the camshaft to be rotated. Severe piston and valve damage will occur.

CAUTION

Rotate the crankshaft counterclockwise only. Do not rotate past position shown or severe piston or valve damage will occur.

NOTE

The number one cylinder is at top dead center (TDC) when the stud on the engine block fits into the slot in the handle of the special tool.

Fig. Rotate the left camshaft sprocket until the timing mark is approximately at the 12 o'clock position. Rotate the right camshaft timing sprocket until the timing mark is approximately at the 11 o'clock position-4.6L DOHC engine

Using special tool 303-448, position the crankshaft so the number one cylinder is at TDC.

Fig. Using special tool 303-448, position the crankshaft so the number one cylinder is at TDC-4.6L DOHC engine

Remove the special tool.

Position the left (inner) timing chain on the crankshaft sprocket, aligning the copper (marked) link with the timing mark on the sprocket.

Fig. Position the left (inner) timing chain on the crankshaft sprocket, aligning the copper (marked) link with the timing mark on the sprocket-4.6L DOHC engine

Install the left timing chain onto the camshaft sprocket, aligning the copper (marked) link with the timing marks on the sprocket.

NOTE

The left timing chain tensioner arm has a bump near the dowel hole for identification.

Fig. Install the left timing chain onto the camshaft sprocket, aligning the copper (marked) link with the timing marks on the sprocket-4.6L DOHC engine

Position the left timing chain tensioner arms on the dowel pin and install the left timing chain tensioner.

On engine with ratcheting timing chain tensioners only, remove the retaining clip from the left timing chain tensioner.

On engine with non-ratcheting timing chain tensioners only, remove the retaining clip from the left timing chain tensioner.

Position the right (outer) timing chain on the crankshaft sprocket, aligning the copper (marked) link with the timing mark on the sprocket.

Install the right timing chain onto the camshaft sprocket, aligning the copper (marked) link with the timing marks on the sprocket.

Fig. Position the right (outer) timing chain on the crankshaft sprocket, aligning the copper (marked) link with the timing mark on the sprocket-4.6L DOHC engine

Fig. Install the right timing chain onto the camshaft sprocket, aligning the copper (marked) link with the timing marks on the sprocket-4.6L DOHC engine

Position the right timing chain tensioner arms on the dowel pin and install the right timing chain tensioner.

On engine with ratcheting timing chain tensioners only, remove the retaining clip from the right timing chain tensioner.

On engine with non-ratcheting timing chain tensioners only, remove the retaining clips from the right timing chain tensioner.

NOTE

Applies to all engine.

Make sure that the copper (marked) chain links are lined up with the dots on the crankshaft sprockets and the camshaft sprocket.

Fig. Make sure that the copper (marked) chain links are lined up with the dots on the crankshaft sprockets and the camshaft sprocket-4.6L engine

4.6L (VIN W) SOHC Engine

Before servicing the vehicle, refer to the precautions in the beginning of this manual.

Remove or disconnect the following:

WARNING

Since the engine is not free-wheeling, timing procedures must be followed exactly or piston and valve damage may occur.

Front cover

Crankshaft sensor ring from the crankshaft

Rotate the crankshaft until both camshaft key ways are 90 degrees from the valve cover surface. Make sure the copper links line up with the dots on the camshaft sprocket.

Install the special tools 303-380 and 303-413 on the camshaft.

Remove or disconnect the following:

Left timing chain tensioner

Right timing chain tensioner

Left and right timing chain tensioner arm from the dowel pins

Timing chains and crankshaft sprocket

Timing chain guides

To install:

WARNING

Do not compress the ratchet assembly. This will damage the ratchet assembly.

Compress the tensioner plunger, using an edge of a vise.

Using a small screwdriver or pick, push back and hold the ratchet mechanism.

While holding the ratchet mechanism, push the ratchet arm back into the tensioner housing.

Install a paper clip into the hole in the tensioner housing to hold the ratchet assembly and plunger in during installation.

NOTE

If the copper links are not visible, mark one link on one end and one link on the other end, and use as timing marks.

Install or connect the following:

Crankshaft sprocket, making sure the timing mark faces forward

Timing chain guides

Left (inner) timing chain on the crankshaft sprocket, aligning the copper link with the dot on the crankshaft sprocket

Left (inner) timing chain on the camshaft sprocket, aligning the copper link with the dot on the camshaft sprocket

Fig. Copper link alignment-4.6L SOHC Engine

Fig. Left cylinder head bolt torque sequence 4.6L SOHC Engine

Right (outer) timing chain on the crankshaft sprocket, aligning the copper link with the dot on the crankshaft sprocket

Right (outer) timing chain on the camshaft sprocket, aligning the copper link with the dot on the camshaft sprocket

Make sure that the copper marks on the timing chain are lined up with the corresponding dots on the crankshaft sprockets and the camshaft sprockets.

Fig. Sprocket alignment-4.6L SOHC Engine

Make sure that the camshaft sprocket keyway is 90 degrees from the valve cover mounting surface.

NOTE

The left timing chain tensioner arm has a bump near the dowel hole, for identification.

Position the left and right timing chain tensioner arm on the dowel pins.

Position the right timing chain tensioner and install the bolts.

Position the left timing chain tensioner and install the bolts.

Remove both the right and left retaining pins from the timing chain tensioner.